Investigation of the Aroma Profile of Green Tea Leaves Using Organic Synthesis and Conventional Analytical Techniques

Although many aroma components have been identified in green tea leaves, the aroma compounds contributing to green tea＇s characteristic odor have not yet been reported. The authors recently reported that aroma components with a matcha-like odor are present in both green tea and black tea prepared from the Sayamakaori tea cuttivar. This matcha-like odor is similar to the odor of commercial available matcha （high-quality powdered green tea）, and is a specific odor feature of green tea leaves. At present, the green-tea odor is thought to arise from the combination of a large number of constituents. Recent reports indicate that a complex interaction between olfactory receptors and odorants is important for the evaluation of the odors. Taking into consideration these findings, the authors investigated the aroma profile of green tea, focusing on the characteristic molecular structures of the constituents that give matcha-like odor. Using a combination of organic synthesis and gas chromatography-mass spectrometry plus gas chromatography-olfactometry, the authors identified aroma components with matcha-like odors in five other tea cultivars. This investigation also revealed that several compounds with a formyl group were important constituents of the aroma of green tea leaves, although the odor of each constituent was not individually similar to the tea＇s overall aroma. The authors found for the first time a group of key components that have the matcha-like odor.

Sliding Mode Controller for Three-Phase Hybrid Active Power Filter with Photovoltaic Application

This paper presents a new three-phase hybrid active power filter configuration that interconnects a passive high-pass filter in parallel with an active power filter and a photovoltaic system. The proposed configuration can improves the filtering performance of the conventional active power filter, as well as simultaneously supply the power from the photovoltaic arrays to the load and utility. This paper will describe the proposed hybrid active power filter control using sliding mode with photovoltaic system. The proposed technique effectively filters harmonics under 1 kHz but also higher frequency to achieve wideband harmonics compensation. The THD of source current is reduced from 30.09% to 1.95%. The result indicates that the sliding mode controller can track the reference signals and have good dynamic characteristics.

Impact of Industrial Pollution on the Zooplankton Population Diversity of the Hammam Boughrara Dam

Works concerning zooplankton of freshwaters of the western area of Algeria are only very fragmentary and remain at an embryonic state. Remediating to this situation, it led a study of the biodiversity and zooplanktonic populations distribution in time and space in the Boughrara dam lake which remains subject to a strong pollution coming essentially from Morocco. The preliminary results of the faunistic analysis of the zooplanktonic populations enabled to highlight an important richness of zoological groups. The CFA （correspondences factorial analysis） and the AHC （ascending hierarchical classification） methods used both enabled to define the species distribution of both open waters and littoral ones, and also to perform existing affinities between them and the state of the used medium. Compared to other barrages, such as those of Bouhanifia and of Sarno, the zooplanktonic populations of both open waters and littoral populations appear to a great extent numerous in rain period. On the quantitative and qualitative level, the zooplanktonic populations strongly suffer from the pollution contamination coming from the Mouillah River especially in summer period. It is time to think about the protection of this fauna which is the second trophic chain link and this intending to preserve the ecosystems in an equilibrium state and to consider the exploitation of natural resources in the realization of an aquacultural farm.

Temperature Variations in Sidi Bel Abbes during the Last Three Decades

The Mediterranean climate of the Sidi Bel Abbes city in northwestern Algeria has not been the subject of many investigations except some sporadic syntheses reports. However, climate change studying its most important parameters has not, at our knowledge, been the subject of a rigorous study. For this purpose this work intends to gather several temperatures ranging between 1980 and 2006 and find a mathematical model that tells us climate changes following changes in temperature during this time interval. Consequently and undesirably, the results confirm firmly the global greenhouse effect affecting our planet, but what seems rather puzzling is the fact that this warming trend has accelerated over time resulting in a changing climate toward warmer periods, for that reason a likely shift in the region of a semi-arid to tropical or arid regime overall, depending mainly on the evolution of the Azores anticyclone.

Protective and therapeutic effect of protocatechuic acid in assessment of letrozole- induced polycystic ovary syndrome in rats

Objective:To investigate the potential activity of protocatechuic acid in female Wistar rats with letrozole-induced polycystic ovary syndrome(PCOS).Methods:Thirty rats were divided into five groups of six each.Group 1 received 0.5%carboxy methyl cellulose orally and served as the normal control group;group 2 was treated orally with 1 mg/kg of letrozole daily for 21 days and served as the PCOS induced group;group 3 was orally administered with letrozole of 1 mg/kg for 21 days and further administered with standard drug of clomiphene citrate at a dose of 1 mg/kg body weight in 0.5%carboxy methyl cellulose per oral and served as the standard group;groups 4 and 5 were administered with letrozole of 1 mg/kg for 21 days and further treated with protocatechuic acid orally at low dose of 5 mg/kg body weight and high dose of 15 mg/kg body weight respectively for 15 days.At the end of the study period,rats were subjected for the estimation of invasive blood pressure and heart rate,biochemical estimations and antioxidant assay.In addition,ovarian histomorphology was examined.Results:The PCOS was confirmed in the letrozole induced rats with increased concentration of androgen,abnormal lipid levels,glucose,glycosylated haemoglobin and also depletion of antioxidants.After protocatechuic acid treatment,the increased levels of testosterone due to induction of PCOS were restored to normal levels.Additionally,there was a consistent decrease in luteinizing hormone and follicle stimulating hormone levels in the treatment groups,followed by decrease in the number of cysts after treatment with protocatechuic acid.Histopathological observations showed a remarkable recovery of the ovarian tissue and the presence of normalized structure of antral follicle.Protocatechuic acid treatment restored all the parameters to normalcy and abolished cysts formation in ovaries of female rats.Conclusions:Protocatechuic acid shows potential protective effects in letrozole-induced PCOS rats.The protective effect is comparable to that of clomiphene citrate and thus shows its potential in the treatment of PCOS.

Nitrogen Discharged from the Earth’s Interior Regions

The abundant nitrogen in the Earth’s atmosphere can be interpreted as the result of endothermic nuclear transmutation of carbon and oxygen atom pairs in (Ca, D) CO3 or CaCO3 aragonite lattice of Earth’s crust from the Archean era to the present time, by physical catalytic help of excited electrons e* generated by stick sliding due to plate tectonics and geoneutrinos ν by the radioactive decay of elements such as uranium and thorium in Earth’s mantle: through a nuclear attraction effect that is due to deuteron catalysis of nitrogen formation. The relationship between the critical temperature T and the critical pressure P for the nuclear transmutation is expressed as 7253 × e-0.014P, and the formation of nitrogen in the mantle is possible at temperatures ≥ 2510 K and pressure ≥ 58 GPa.

Heteropoly Ionic Liquid Functionalized MOF-Fe:Synthesis,Characterization,and Catalytic Application in Selective Acetalization of Glycerol to Solketal as a Fuel Additive at Room Temperature,Solvent-Free Conditions

In this work,we have reported the synthesis of a series of heterogeneous catalysts,viz.,[HMIm]_(3)[PW_(12)O_(40)]@MOF-Fe,[HMIm]_(3)[PMo_(12)O_(40)]@MOF-Fe,and[HMIm]_(4)[SiW_(12)O_(40)]@MOFFe,by a simple impregnation method.The catalysts were characterized by several techniques,such as FTIR,EDX,XRD,SEM,elemental mapping,and TGA.Among these materials,[HMIm]_(3)[PW_(12)O_(40)]@MOF-Fe had more acidic sites(confirmed by potentiometric titration)and high stability around 598℃(confirmed by TGA).The catalytic prospect of the materials was examined through selective acetalization of glycerol to solketal as a fuel additive under solvent-free and room-temperature conditions.[HMIm]_(3)[PW_(12)O_(40)]@MOF-Fe exhibited the highest catalytic activity among the three catalysts in terms of glycerol conversion(100%),solketal selectivity(100%),and solketal yield(100%).A recyclability study of[HMIm]_(3)[PW_(12)O_(40)]@MOF-Fe showed that the material could be reused for up to 7 cycles with insignificant loss in its catalytic performance.

Multispectral harvesting rare-earth oxysulphide based highly efficient transparent luminescent solar concentrator

Transparent luminescent solar concentrator(LSC)is extensively regarded as the most promising sunlight tapping device for its application in buildings integrated with photovoltaics(BIPV)or as solar window glass.Conventional LSCs doped with organic dyes suffered from high reabsorption losses with no transparency;whereas,recently reported heavy metal-doped quantum dots avoided such losses but possessed the risk of high toxicity and low ambient stability.Thus,luminophores with massive spectral shifts and co rdial relationships with the enviro nment are very much desirable.In this paper,we report the fabrication of PMMA based transparent LSC embedded with nanocrystals of environmental friendiness and multispectral harvesting gadolinium oxysulphide(Gd_(2)O_(2) S:Er,Yb)fluorophore.The Gd_(2)O_(2) S:Er,Yb nanofluorophore absorbs various excitation wavelengths ranging from UV to NIR and emits in the visible region offering huge Stoke’s and anti-Stoke’s shift concurrently.The non-existent reabsorption losses and overlapping maxima of Gd_(2)O_(2) S:Er,Yb nanofluorophore generated photon flux with solar cells’responsivity enhance the efficiency characteristics of the LSC waveguide.Performance analysis of LSC as a function of varying nanofluorophore dispersion ratio and changing edge width optimizes the fabrication process and exhibits high power conversion efficiency of-6,93%and optical efficiency of-8.57%.The LSC slab demonstrates high photostability under irradiation for prolonged hours without any dip in the emission characteristics.The Gd_(2)O_(2) S:Er,Yb nanofluorophore diffused LSC waveguide offering spectral tunability,cost-reduction,efficiency enhancement,and high concentration factor whilst being sustainable for long term use makes it a fascinating transparent solar window.

Anodic-biased titania nanotube growth in low-dielectric viscous media

The influence was investigated of aqueous electrolytes and organic-based electrolytes on nanopore growth.To create well-defined nanotubes with a high aspect ratio,it is important to maintain equilibrium between field-assisted metal oxide dissolution and field-assisted water dissociation,which influence the temperature and pH levels in TiO_(2) nanotubes(TiO_(2) NTs).This sought after balance in the net reactions of the TiO_(2) NT growth can be achieved by choosing the appropriate electrolytes that are a relatively low dielectric viscous media.Viscosity(η)and dielectrics(ε)can be a priority in designing the experiment since it is closely related to joule-heating,diffusion-driven metal ions dissolution and chemical etching of the metal oxide.Solvation and the hydrogen bonding ability are inter-correlated to the stability of the[TiF_(6)]^(2-) complex.In order to examine various electrolyte effects on the anodic-biased nanotube,different categories of electrolytes,each with different viscosity and dielectric properties,were incorporated in this study.